src/Core/Hook.php

   1 <?php
   2 /**
   3  * @file src/Core/Hook.php
   4  */
   5 namespace Friendica\Core;
   6
   7 use Friendica\App;
   8 use Friendica\BaseObject;
   9 use Friendica\Database\DBA;
  10
  11 /**
  12  * Some functions to handle hooks
  13  */
  14 class Hook extends BaseObject
  15 {
  16         /**
  17          * Array of registered hooks
  18          *
  19          * Format:
  20          * [
  21          *              ["<hook name>"] => [
  22          *                      0 => "<hook file>",
  23          *                      1 => "<hook function name>"
  24          *              ],
  25          *              ...
  26          * ]
  27          *
  28          * @var array
  29          */
  30         private static $hooks = [];
  31
  32         /**
  33          * Load hooks
  34          */
  35         public static function loadHooks()
  36         {
  37                 self::$hooks = [];
  38                 $stmt = DBA::select('hook', ['hook', 'file', 'function'], [], ['order' => ['priority' => 'desc', 'file']]);
  39
  40                 while ($hook = DBA::fetch($stmt)) {
  41                         if (!array_key_exists($hook['hook'], self::$hooks)) {
  42                                 self::$hooks[$hook['hook']] = [];
  43                         }
  44                         self::$hooks[$hook['hook']][] = [$hook['file'], $hook['function']];
  45                 }
  46                 DBA::close($stmt);
  47         }
  48
  49         /**
  50          * Registers a hook.
  51          *
  52          * @param string $hook     the name of the hook
  53          * @param string $file     the name of the file that hooks into
  54          * @param string $function the name of the function that the hook will call
  55          * @param int    $priority A priority (defaults to 0)
  56          * @return mixed|bool
  57          */
  58         public static function register($hook, $file, $function, $priority = 0)
  59         {
  60                 $file = str_replace(self::getApp()->getBasePath() . DIRECTORY_SEPARATOR, '', $file);
  61
  62                 $condition = ['hook' => $hook, 'file' => $file, 'function' => $function];
  63                 if (DBA::exists('hook', $condition)) {
  64                         return true;
  65                 }
  66
  67                 $result = DBA::insert('hook', ['hook' => $hook, 'file' => $file, 'function' => $function, 'priority' => $priority]);
  68
  69                 return $result;
  70         }
  71
  72         /**
  73          * Unregisters a hook.
  74          *
  75          * @param string $hook     the name of the hook
  76          * @param string $file     the name of the file that hooks into
  77          * @param string $function the name of the function that the hook called
  78          * @return boolean
  79          */
  80         public static function unregister($hook, $file, $function)
  81         {
  82                 $relative_file = str_replace(self::getApp()->getBasePath() . DIRECTORY_SEPARATOR, '', $file);
  83
  84                 // This here is only needed for fixing a problem that existed on the develop branch
  85                 $condition = ['hook' => $hook, 'file' => $file, 'function' => $function];
  86                 DBA::delete('hook', $condition);
  87
  88                 $condition = ['hook' => $hook, 'file' => $relative_file, 'function' => $function];
  89                 $result = DBA::delete('hook', $condition);
  90                 return $result;
  91         }
  92
  93         /**
  94          * Returns the list of callbacks for a single hook
  95          *
  96          * @param  string $name
  97          * @return array
  98          */
  99         public static function getByName($name)
 100         {
 101                 $return = [];
 102
 103                 if (isset(self::$hooks[$name])) {
 104                         $return = self::$hooks[$name];
 105                 }
 106
 107                 return $return;
 108         }
 109
 110         /**
 111          * @brief Forks a hook.
 112          *
 113          * Use this function when you want to fork a hook via the worker.
 114          *
 115          * @param string       $name of the hook to call
 116          * @param string|array $data to transmit to the callback handler
 117          */
 118         public static function fork($priority, $name, $data = null)
 119         {
 120                 if (array_key_exists($name, self::$hooks)) {
 121                         foreach (self::$hooks[$name] as $hook) {
 122                                 Worker::add($priority, 'ForkHook', $name, $hook, $data);
 123                         }
 124                 }
 125         }
 126
 127         /**
 128          * @brief Calls a hook.
 129          *
 130          * Use this function when you want to be able to allow a hook to manipulate
 131          * the provided data.
 132          *
 133          * @param string       $name  of the hook to call
 134          * @param string|array &$data to transmit to the callback handler
 135          */
 136         public static function callAll($name, &$data = null)
 137         {
 138                 if (array_key_exists($name, self::$hooks)) {
 139                         foreach (self::$hooks[$name] as $hook) {
 140                                 self::callSingle(self::getApp(), $name, $hook, $data);
 141                         }
 142                 }
 143         }
 144
 145         /**
 146          * @brief Calls a single hook.
 147          *
 148          * @param App $a
 149          * @param string         $name of the hook to call
 150          * @param array          $hook Hook data
 151          * @param string|array   &$data to transmit to the callback handler
 152          */
 153         public static function callSingle(App $a, $name, $hook, &$data = null)
 154         {
 155                 // Don't run a theme's hook if the user isn't using the theme
 156                 if (strpos($hook[0], 'view/theme/') !== false && strpos($hook[0], 'view/theme/' . $a->getCurrentTheme()) === false) {
 157                         return;
 158                 }
 159
 160                 @include_once($hook[0]);
 161                 if (function_exists($hook[1])) {
 162                         $func = $hook[1];
 163                         $func($a, $data);
 164                 } else {
 165                         // remove orphan hooks
 166                         $condition = ['hook' => $name, 'file' => $hook[0], 'function' => $hook[1]];
 167                         DBA::delete('hook', $condition, ['cascade' => false]);
 168                 }
 169         }
 170
 171         /**
 172          * check if an app_menu hook exist for addon $name.
 173          * Return true if the addon is an app
 174          */
 175         public static function isAddonApp($name)
 176         {
 177                 if (array_key_exists('app_menu', self::$hooks)) {
 178                         foreach (self::$hooks['app_menu'] as $hook) {
 179                                 if ($hook[0] == 'addon/' . $name . '/' . $name . '.php') {
 180                                         return true;
 181                                 }
 182                         }
 183                 }
 184
 185                 return false;
 186         }
 187 }